Don Stranathan and Penny Blume are middle-aged lovers spending a glorious month traveling on the West Coast, savoring each moment as if it were their last. And it may be; both have terminal lung cancer.

Stranathan, 60, works for an office technology company and is an avid hiker from Santa Rosa, Calif., and Blume, 50, is a former waitress from Sullivan County, N.Y.

They juggle bicoastal cancer treatments and cross-country flights with their budding romance, one that started in 2011 in the online medical community Inspire.

They checked out each other's profiles and eventually she "friended" him on Facebook.

"We started chatting back and forth, different messages each day," Stranathan said. "At one time, I had over 5,000 text messages and they were mostly all with Penny.

"We weren't looking for a relationship, but we surprised each other," he said.

Inspire was an unlikely place for love to blossom. It builds online health and wellness communities for patients and care givers in partnership with national patient advocacy organizations, putting its 260,000 members in touch with other for support and research information.

"It's about the furthest thing from a dating site as you can find," said John Novack, the company's communications director. "They are unusual in the social network world."

He spotted the open letter they posted to online friends, declaring, "We want to spend the rest of our lives together."

By December, the couple arranged to meet in person in California. Blume's girlfriend was suspicious, teasing her, "Most people meet in a public place, but you go across country."

Since then, Blume has made three trips west and Stranathan has done the same, east.

"One of the biggest challenges is trying to get together around treatment," she said.

Blume, the mother of two adult boys, was talking marriage with another man when she got her grim diagnosis.

For six months, she had been having trouble breathing and thought it was her asthma. An X-ray revealed a significant mass on her lungs that turned out to be small-cell cancer in an "extensive" stage.

She was devastated and so was the boyfriend. "He walked out on me a week before we were talking about getting married," Blume said. "He said, 'I don't love you anymore.'"

But after ablation surgery on her adrenal gland and liver at Memorial Sloan-Kettering Cancer Center in New York, where Blume is being treated, she awoke to a surprise.

"When I came out of recovery and got into the room, flowers were awaiting me," she said. "They were from Don."

Stranathan, divorced with an adult son and daughter and grandchildren, never suspected he had lung cancer until he was required to have a chest X-ray for tuberculosis while volunteering in a drug and alcohol recovery program with inmates at San Quentin in 2009.

Doctors found a suspicious spot on one lung, then later on the other.

"A week before, I had hiked 21 miles and people with me said they thought I was short of breath," he said. "The only reason my lung didn't collapse was a do a lot of exercise."

Stranathan said he had also been in a relationship that fell apart. "She knew I had lung cancer and at some point didn't want to deal with it," he said.